AbstractA number of addition reactions to diphenylmethylenecyclopropane (II) have been studied. Bromination and CF3COOH addition in CH3Cl2proceeded with ring‐opening and gave the homoallylic adducts III and VI. On the other hand bromination in glyme and water gave both unrearranged and rearranged products, III and V. Reactions with NBS in the same solvent system gave the unrearranged bromohydrin V. Oxymercuration and hydroboration proceeded without ring‐cleavage, the mercury and boron attacking mainlyβ‐ to the phenyl groups. Two cyclopropylmercury compounds VII and IX were isolated and charact